Sawatari is son of a high-ranking official in Maiami City and a student of Leo Institute of Dueling. After losing to Yuuya Sakaki for the first time, he vows to defeat him and becomes his rival. Sawatari is initially shown to have an inflated ego as a "Perfect Duelist", being selfish, pompous, and incredibly egotistical, enjoying being praised by his crew and showing off in front of everyone, although he doesn't take kindly to anyone who interrupts him. His defeat at Yuuya's hands caused him to develop a grudge against him, but also caused him to develop some of his mannerisms, also starting to enjoy entertaining the crowd and encouraging Yuuya to do the same. Sawatari also often makes gestures relating to darts when he feels they suit the situation.

He is also shown to be extremely materialistic, valuing only rare cards. This is shown in his Decks which are initially comprised of only Parallel Rare cards. Furthermore he seems to be quite shallow with cards, judging them solely for their ATK or DEF values and their Level regardless of what effect they may have. He has a tendency to use his father in an attempt to gain an advantage in certain situations, such as threatening him to make him people lose their jobs.

He later becomes one of the Lancers after getting another chance from Reiji, and obtains a new deck.